fix #1259 #1260 #753

spring-cloud-alibaba-starters/spring-cloud-starter-dubbo/src/main/java/com/alibaba/cloud/dubbo/metadata/repository/DubboServiceMetadataRepository.java

@@ -16,18 +16,6 @@
 
 package com.alibaba.cloud.dubbo.metadata.repository;
 
-import java.util.Collections;
-import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Set;
-import java.util.stream.Collectors;
-import java.util.stream.Stream;
-
-import javax.annotation.PostConstruct;
-
 import com.alibaba.cloud.dubbo.env.DubboCloudProperties;
 import com.alibaba.cloud.dubbo.http.matcher.RequestMetadataMatcher;
 import com.alibaba.cloud.dubbo.metadata.DubboRestServiceMetadata;
@@ -58,15 +46,16 @@ import org.springframework.stereotype.Repository;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
 
+import javax.annotation.PostConstruct;
+import java.util.*;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
 import static com.alibaba.cloud.dubbo.env.DubboCloudProperties.ALL_DUBBO_SERVICES;
 import static com.alibaba.cloud.dubbo.http.DefaultHttpRequest.builder;
 import static java.lang.String.format;
 import static java.lang.String.valueOf;
-import static java.util.Collections.emptyList;
+import static java.util.Collections.*;
-import static java.util.Collections.emptySet;
-import static java.util.Collections.unmodifiableList;
-import static java.util.Collections.unmodifiableMap;
-import static java.util.Collections.unmodifiableSet;
 import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
 import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
 import static org.springframework.util.CollectionUtils.isEmpty;
@@ -289,9 +278,12 @@ public class DubboServiceMetadataRepository
 							serviceName);
 				}
 
-				initSubscribedDubboMetadataService(serviceName);
+
-				// mark this service name having been initialized
+				if (initSubscribedDubboMetadataService(serviceName)){
-				initializedServices.add(serviceName);
+					// mark this service name having been initialized
+					initializedServices.add(serviceName);
+				}
+
 			}
 		}
 	}
@@ -301,11 +293,17 @@ public class DubboServiceMetadataRepository
 	 * service instance.
 	 * @param serviceName the service name
 	 */
-	public void removeMetadataAndInitializedService(String serviceName) {
+	public void removeMetadataAndInitializedService(String serviceName, URL url) {
 		synchronized (monitor) {
 			initializedServices.remove(serviceName);
 			dubboRestServiceMetadataRepository.remove(serviceName);
-			subscribedDubboMetadataServiceURLs.remove(serviceName);
+			// fix #1260 if the subscribedDubboMetadataServiceURLs removed fail，old meta information will be retained
+			if( DubboMetadataService.class
+					.getName().equals(url.getServiceInterface() )) {
+				String serviceKey = url.getServiceKey();
+				subscribedDubboMetadataServiceURLs.remove(serviceKey);
+			}
+
 		}
 	}
 
@@ -614,24 +612,66 @@ public class DubboServiceMetadataRepository
 		subscribedServices.remove(currentApplicationName);
 	}
 
-	protected void initSubscribedDubboMetadataService(String serviceName) {
+	protected Boolean initSubscribedDubboMetadataService(String serviceName) {
-		metadataServiceInstanceSelector.choose(discoveryClient.getInstances(serviceName))
+		// this need to judge whether the initialization is successful or not. The failed initialization will not change the initializedServices
+		Optional<ServiceInstance> optionalServiceInstance = metadataServiceInstanceSelector.choose(discoveryClient.getInstances(serviceName));
+		if(!optionalServiceInstance.isPresent() ){
+			return false;
+		}
+		ServiceInstance serviceInstance = optionalServiceInstance.get();
+		if(null == serviceInstance ){
+			return false;
+		}
+		List<URL> dubboMetadataServiceURLs = getDubboMetadataServiceURLs(serviceInstance);
+		if(dubboMetadataServiceURLs.isEmpty()){
+			return false;
+		}
+		for(URL dubboMetadataServiceURL : dubboMetadataServiceURLs){
+			try {
+				initSubscribedDubboMetadataServiceURL(
+						dubboMetadataServiceURL);
+				DubboMetadataService dubboMetadataService = dubboMetadataConfigServiceProxy.getProxy(serviceName);
+				if(dubboMetadataService == null){
+					dubboMetadataService = initDubboMetadataServiceProxy(dubboMetadataServiceURL);
+				}
+
+				if(dubboMetadataService == null){
+					removeMetadataAndInitializedService(serviceName, dubboMetadataServiceURL);
+					return false;
+				}
+			}
+			catch (Throwable e) {
+				if (logger.isErrorEnabled()) {
+					logger.error(e.getMessage(), e);
+				}
+			}
+		}
+		/*metadataServiceInstanceSelector.choose(discoveryClient.getInstances(serviceName))
 				.map(this::getDubboMetadataServiceURLs)
 				.ifPresent(dubboMetadataServiceURLs -> {
-					dubboMetadataServiceURLs.forEach(dubboMetadataServiceURL -> {
+					if( dubboMetadataServiceURLs.isEmpty()){
-						try {
+						initializedServices.remove(serviceName);
-							initSubscribedDubboMetadataServiceURL(
+					}else{
-									dubboMetadataServiceURL);
+						dubboMetadataServiceURLs.forEach(dubboMetadataServiceURL -> {
-							initDubboMetadataServiceProxy(dubboMetadataServiceURL);
+							try {
-						}
+								initSubscribedDubboMetadataServiceURL(
-						catch (Throwable e) {
+										dubboMetadataServiceURL);
-							if (logger.isErrorEnabled()) {
+								DubboMetadataService dubboMetadataService = initDubboMetadataServiceProxy(dubboMetadataServiceURL);
-								logger.error(e.getMessage(), e);
+								if(dubboMetadataService == null){
+									initializedServices.remove(serviceName);
+								}
 							}
-						}
+							catch (Throwable e) {
-					});
+								if (logger.isErrorEnabled()) {
-				});
+									logger.error(e.getMessage(), e);
+								}
+							}
+						});
+					}
+
+				});*/
 		initDubboRestServiceMetadataRepository(serviceName);
+		return true;
 	}
 
 	private void initSubscribedDubboMetadataServiceURL(URL dubboMetadataServiceURL) {
@@ -640,11 +680,12 @@ public class DubboServiceMetadataRepository
 		subscribedDubboMetadataServiceURLs.add(serviceKey, dubboMetadataServiceURL);
 	}
 
-	private void initDubboMetadataServiceProxy(URL dubboMetadataServiceURL) {
+	private DubboMetadataService initDubboMetadataServiceProxy(URL dubboMetadataServiceURL) {
 		String serviceName = dubboMetadataServiceURL.getParameter(APPLICATION_KEY);
 		String version = dubboMetadataServiceURL.getParameter(VERSION_KEY);
 		// Initialize DubboMetadataService with right version
-		dubboMetadataConfigServiceProxy.initProxy(serviceName, version);
+		return dubboMetadataConfigServiceProxy.initProxy(serviceName, version);
+
 	}
 
 	@Override

spring-cloud-alibaba-starters/spring-cloud-starter-dubbo/src/main/java/com/alibaba/cloud/dubbo/registry/AbstractSpringCloudRegistry.java

@@ -16,14 +16,6 @@
 
 package com.alibaba.cloud.dubbo.registry;
 
-import java.util.Collection;
-import java.util.HashSet;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Set;
-import java.util.function.Function;
-import java.util.stream.Collectors;
-
 import com.alibaba.cloud.dubbo.metadata.repository.DubboServiceMetadataRepository;
 import com.alibaba.cloud.dubbo.registry.event.ServiceInstancesChangedEvent;
 import com.alibaba.cloud.dubbo.service.DubboGenericServiceFactory;
@@ -36,21 +28,20 @@ import org.apache.dubbo.registry.RegistryFactory;
 import org.apache.dubbo.registry.support.FailbackRegistry;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-
 import org.springframework.cloud.client.ServiceInstance;
 import org.springframework.cloud.client.discovery.DiscoveryClient;
 import org.springframework.context.ApplicationListener;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.util.CollectionUtils;
 
+import java.util.*;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
 import static java.util.Arrays.asList;
 import static java.util.Collections.emptyList;
 import static org.apache.dubbo.common.URLBuilder.from;
-import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.*;
-import static org.apache.dubbo.common.constants.CommonConstants.PROTOCOL_KEY;
-import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER_SIDE;
-import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
-import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
 import static org.apache.dubbo.common.constants.RegistryConstants.CATEGORY_KEY;
 import static org.apache.dubbo.common.constants.RegistryConstants.EMPTY_PROTOCOL;
 import static org.apache.dubbo.registry.Constants.ADMIN_PROTOCOL;
@@ -162,6 +153,11 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 		}
 		else if (isDubboMetadataServiceURL(url)) { // for DubboMetadataService
 			subscribeDubboMetadataServiceURLs(url, listener);
+			if( from(url).getParameter(CATEGORY_KEY) != null && from(url).getParameter(CATEGORY_KEY).contains(PROVIDER)){
+				// Fix #1259 and #753 Listene meta service change events to remove useless clients
+				registerServiceInstancesChangedEventListener(url, listener);
+			}
+
 		}
 		else { // for general Dubbo Services
 			subscribeDubboServiceURLs(url, listener);
@@ -241,9 +237,16 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 								+ "available , please make sure the further impact",
 						serviceName, url.getServiceKey());
 			}
-			dubboMetadataConfigServiceProxy.removeProxy(serviceName);
+			if(isDubboMetadataServiceURL(url)){
-			repository.removeMetadataAndInitializedService(serviceName);
+				// if meta service change, and serviceInstances is zero, will clean up information about this client
-			dubboGenericServiceFactory.destroy(serviceName);
+				dubboMetadataConfigServiceProxy.removeProxy(serviceName);
+				repository.removeMetadataAndInitializedService(serviceName, url);
+				dubboGenericServiceFactory.destroy(serviceName);
+				String listenerId = generateId(url);
+				// The metaservice will restart the new listener. It needs to be optimized to see whether the original listener can be reused.
+				this.registerListeners.remove(listenerId);
+			}
+
 			/**
 			 * URLs with {@link RegistryConstants#EMPTY_PROTOCOL}
 			 */
@@ -255,6 +258,11 @@ public abstract class AbstractSpringCloudRegistry extends FailbackRegistry {
 			listener.notify(allSubscribedURLs);
 			return;
 		}
+		if( isDubboMetadataServiceURL(url) ){
+			// Prevent duplicate generation of DubboMetadataService
+			return;
+		}
+		repository.initializeMetadata(serviceName);
 
 		DubboMetadataService dubboMetadataService = dubboMetadataConfigServiceProxy
 				.getProxy(serviceName);